Assessment of cell mediated immune response in rabbits immunized with affinity purified 35 kDa midgut antigen of Rhipicephalus haemaphysaloides ticks.

Cell mediated immune response to immunoaffinity chromatography purified midgut antigen of Rhipicephalus haemaphysaloides ticks in rabbits was studied by using lymphocyte transformation test. This test was carried out by using 5-bromo-2'-deoxy-uridine kit method. The blastogenic response of peripheral blood lymphocytes of normal rabbit to different concentrations of antigen and mitogen (Con A) showed that 2 μg of antigen and 2 μg of mitogen gave maximum stimulation index. The antigen specific responsiveness of immunized rabbits with affinity purified 35 kDa midgut antigen was highly significant (P ≤ 0.01) compared to mitogen. The maximum lymphocyte stimulation index (LSI) of 2.47 was observed on 49 day post immunization in immunized group. The lymphocytes separated from control animal cultured in RPMI1640 medium with 2 μg of antigen and 2 μg of mitogen (Con A) were never stimulated and their LSI values were below 2.0.